In the manufacture Steel is probably the most versatile material used in manufacturing due to its strength, availability, and relatively low cost. However, there is such a variety of different types and treatments of steel that not all types can be machined the same way. Have you ever ordered CNC-machined steel parts and were disappointed? This was likely due to an incorrect choice of material and/or machining parameters.
This blog post is written especially for engineers and purchasing and project managers that are interested in learning about how precision CNC machining is related to steel.
Steel Isn't Just Steel
Visit any steel distributor and you will encounter a wide range of steel grades that have their unique characteristics of machinability, hardness, tensile strength, and heat treatability. Incorrect choices here result in loss of time and money.
Below is a brief description of popular steel grades and their application in CNC machining:
Mild Steel (A36, S235, Etc.) Mild steel is one of the most common and cost-effective types. It has good machinability and weldability, but poor resistance to corrosion. It is used for manufacturing frames and other structures that need surface coatings afterward.
Carbon Steel (1018, 1045). More durable than mild steel. While 1018 provides good machinability and is good for manufacturing shafts and pins, 1045 has higher strength thanks to heat treatment and can be used for manufacturing gears and other mechanical parts.
Alloy Steel (4140, 4340, Etc.) Alloy steels are popular for use in industrial CNC steel parts. In particular, the 4140 grade offers good machinability in annealed conditions as well as mechanical properties in the heat-treated state. They are usure of many parts, from hydraulic parts to valve bodies.
Stainless Steel (304, 316) Not classified as carbon steel, yet it is an essential type. Unlike
How Precision CNC Machining Handles Steel
Why Tolerances Matter in Steel Parts
The steel parts for industry often have to interact with other machinery; shafts interfacing with bearings, bolts screwing into housing holes, and flanges mating with gaskets. To achieve such precise fit and function, the tolerances cannot be maintained by manual or conventional milling.
With CNC machining, all axes of the machine tool's motion are computer controlled and maintained with tolerance throughout the duration of manufacturing. Whereas manual milling could deviate by as much as half a millimeter during extended operation, CNC machines are able to maintain calibration for every unit produced.
This is why CNC steel parts require precision because:
- A 0.05mm variance on the diameter of a shaft would result in poor interfacing with the bearing
- The screw holes need perfect calibration; otherwise, there would be a lot of problems putting together the part
Conclusion
The best CNC steel parts begin with good material selection, along with careful and properly planned processing techniques. The use of precision CNC machining technology ensures the tolerances required for your component throughout the whole batch of parts produced.
FAQs
What steel grades does Genesis-MFG work with?
We machine a wide range, including mild steel, 4140/4340 alloy steels, stainless steel grades (304, 316), and specialty alloys depending on project requirements.
Can you supply material certificates with machined steel parts?
Yes. For applications that require traceability, we can provide mill certificates with material supply.
Do you offer heat treatment as part of your service?
We coordinate heat treatment through trusted partners when required, and sequence our machining operations accordingly.
What's the smallest and largest steel part you can machine?
We handle a range of part sizes. Contact us with your drawings or specifications and we'll confirm capability for your specific application.
